Device for accurately positioning and guiding guide wires used in the nailing of thefemoral neck



Dec. 21, 1954 M. A. ZEHNDER 2,697,433

DEVICE FOR ACCURATELY POSITIONING AND GUIDING GUIDE WIRES USED IN THE NAILING OF THE FEMORAL NECK Filed Dec. 4, 1951 2 Sheets-Sheet 1 INVENTOR. MAX A. ZEHNDER HIS ATTORNEYS.

Dec. 21, 1954 M. A. ZEHNDER 2,697,433

DEVICE FOR ACCURATELY POSITIONING AND GUIDING GUIDE WIRES USED IN THE NAILING OF THE FEMORAL NECK Filed Dec. 4, 1951 2 Sheets-Sheet 2 44 45 n 45 39 36 6/ 5/ 60 n K*" 2/ 5o 'i /9 ii 42 37 :E /5 2 5" 43 e3 J *r i ,3 1 l 3/01 72 4/ 40 25 as so U INVENTOR.

MAX A. ZEHNDER (544w. (MM- 414M H IS ATTORNEYS.

DEVICE FQR ACCURATELY POSITIONING AND GUIDING GUIDE WIRES USED IN'THE NAILING OF THE FEMORAL NECK Max A. Z-ehntler, Jersey City, N. J.

Application December 4, 1951, Serial No. 259,782

Claims. (Cl. 128-83) This invention relates to devices for positioning guide wires used in nailing the femoral neck and it relates particularly to a protractor mechanism whereby the guide wire can be positioned and inserted transcutaneously into the central axis of the bone by means of X-ray examina tion in two mutually perpendicular planes.

The present invention is an improvement over the device disclosed in my Swiss Patent No. 240,542 dated April 16, 1946.

In my earlier device, as disclosed in the above mentioned Swiss patent, it was found that the base of the device does not form a sufficiently stable support for proper insertion of the guide pin and it does not have sufficient flexibility in adiustment to allow the pin to be properly aligned with the axis of the bone without, in many cases. requiring shifting the entire device.

In accordance 'with the present invention, I have provided a supporting frame for a pair of right angularly related protractors which permits shifting of the entire protractor assembly in right angularly related directions and permits rotation of the protractor elements so th t the guide tube for the guide ire may be positionedwith a high degree of accuracy with respect to the axis of the bone. The improved device also includes mechanism giving a greater freedom of adiustment of the guide tube relative to the protract r elements and includes improved means for supporting the guide tube for universal adjustment in its supporting base or frame.

Other improvements and advantages will become apparent from the following description of typical devices embodying the present invention.

S s Pa n 0 For a better understanding of the present invention reference may be had to the accompanying drawings in which:

Figure 1 is a view in side elevation of a typical device embodying the present invention with positioning and guide wires shown therein in dotted lines;

Figure 2 is a view in end elevation of the device shown in Figure l;

Figure 3 is a view in the section on the line 33 of Figure l;

'Figure 4 is a view in the section taken on line 4----4-of Figure 3;

Figure 5 is a'v'iew in the section taken on line '55 of Figure 3;

Figure 6 is a view in the section taken on line 6-6 of Figure 3;

Figure 7 is a pers ective view of a portion of the protractors and the guide tube for inserting the guide wire illustrating a modified form of adjusting and locking mechanism; and

Figure 8 is a view in the section illustrating'a modified form of supporting ring and ball retainer for the protractor and the guide tube.

Each nail positioning device described hereafter is of a type which is attached to the fractured member and positioned so that the guide wire is introduced transcutaneously along the axis of the femoral neck. For ex ample, the device may be attached to-the thigh over the trochanter by means of positioning pins or wires such as Kirschner wires driven into the bone. To enable the device to be so attached, it includes, as shown in Figures 1-3, a rectangular base 'frame member 10 which forms a supporting framework for the other elements referred to hereafter. The opposite ends 10a-and'1'0bof theframe 10 may, as shown' in Figure 2,'be provided with aplurality of threaded openings 11 to "receive the screws 124E413 which pass through the wire receiving blocks 14 and '15 and secure them to the opposite ends of the frame. The blocks 14 and 15 as shown in Figure 1 may be generally L-s'haped so that their inner ends 14a, for example, rest upon the top of the frame 10 and thereby, are held against tlltlng movement. The pin engaging blocks 14 and 15 may be positioned any place along the ends of the frame 10 where there is a corresponding aperture 11.

The frame 10 is secured to the limb by means of Kirschner wires K which extend through holes 16 and 17 in the blocks 14 and 15 and are driven into the bone. The frame is pressed firmly against the flesh and locked to the pins K by means of the thumb screws 19 and 2.0 which are threaded into the blocks 14 and 15 and engage the wires K.

Mounted upon the frame 10 for adjustment lengthwise thereof is a second frame member 21. The frame member 21 has downwardly extending flanges 22 and 23 which overlap the longitudinal sides 10c and 10d of the frame 10 and carry thumb screws 24 and 25 which engage the sides of the frame below the flanges 26 and 27 at the upper lateral edges of the sides 16c and 10d of the frame 10 as shown in Figs. 1 and 5. By loosening one or both of the thumb screws 24 and 25, the frame 21 may be released for adjustment lengthwise of the frame 10 and thereafter locked in adjusted position by tightening the thumb screws 24 and/or 25.

As best shown in Figure 3, the frame 21 is not a solid frame. One end 30 of the frame is pivotally connected by means of a pivot pin 31 to a side rail 32 of the frame. The opposite end of the pivoted arm 36 carries a thumb screw 33 receivable in a threaded recess 34 in the longitudinal arm 35 of the frame 21. In this way, the thumb screw 33 can 'be backed out to allow the arm 30 to be swung away to receive a carriage 36 providing for transverse adjustment of the device. The carriage 36 is generally square in plan and has a tapered or chainfered edge 37 receivable in a V-shaped groove 38 in the arm 30 of the frame 21. The opposite edge '39 of the carriage 36 has a depending flange 40 thereon provided with a V-shaped rib 41 which is received in a complementary groove 42 in the transverse rail 43 of the frame 21. The carriage 36 is narrower than the width of the frame 21, thereby allowing adjustment of the carriage transversely relative to the longitudinal axis of the frame 10. Transverse adjustment of the carriage 36 may be accomplished by loosening the thumb screw 33 and moving the carriage relative to the frame 21, after which the thumb screw 33 is tightened to grip the carriage between the arm 30 and the cross rail 43 of the frame 21.

The above described frame and carriage structure provides for adjustment of the guide tube 44, through which the guide wire W is introduced transcutaneously into the bone, in two right angularly related directions. The guide tube 44, as shown in Figures 1 to 4, is provided with a ball-like lower end 45 which is rotatably mounted in a ring member 46 mounted rotatablyin the carriage 36. 'The ring member 46'is mounted in a circular hole 47 in the midportion of the carriage 36 and has a flange 48 resting upon a shoulder 49 at the upper edge of the ho1e 47. The ring is retainedi'n the holeby means of a retaining ring 50 which has a lip 51 overlapping theflange 48. The retaining ring 50 is secured to the carriage 3.6 by means of a plurality of screws 52 around its periphery. The ring 46 maybe retained against {rotation by means of a thumb screw 53 threaded through the end 39 of the carriage 36to bear against the'ring 46.

The guide tube '44, as shown in Figures 1 and"2 may bepositioned angularly by means of a pair of protractors 54'and '55. The protractors 54 and 555 are similar and only one of them will be described herein. Protractor '54 includes a pair of spaced apart arcuate bars 56 and 57 which are joined at their ends by spacing-portions 58. The bars 56 and 57 are disposed on opposite sides of the guide tube 44. The protractor "541's supported by means of a pair of rods 59 and 60 which extend downwardly toward the ring 46 from the ends of the bars 56 and 1-57. The rods 59 and 60 support the protractor '54 'for"=rocking movement about an axis passing through formed "on their lower ends to receive rivets 63 and 64 for securing the rods to the. inner surface of the ring 46 with capacity for rocking movement about the axis of the rivets 65 and 64. The eyes 61 and 62 engage the opposite sides of the ball and -when the. heads of the rivets. are countersunk the eyes-form-sockets for partially positioning the. ball and the tube 44 agalnst endwise movement. The ball may be retained further against upward movement by means -of a notched plate 65 which is secured to the ring 46- and overlies a portion of the.ball.45.

The protractor is supportedon the ring 46 m a manner similar-.tothe protractor 54, the only ma or difference being that the rods 66 and 67 thereof are longer than the rods 59, and and the protractor 55 is formed on a correspondingly longer radius of curvature. Itwill be seen that the protractors 54 and 55 are-movable about right angularly related axesand inasmuch-asthe guide tube 44 is movable with the protractors, it "is capable of substantially universal'adjustment with respect to the supporting frame'10. 1

The guide. tube v44- may .be locked-with respect to both of the'protractorelements 5.4 and-55 by means of inner and outer thumb nuts 69 and 70 whichare threaded on the upper threaded ,end 71 ofthe guide tube; By tightening both of the nuts'69 and 70 against theprotractors 54 and 55, the guide tube'may be lockedfirmly in any adjusted position. I

The above described device is used with X-ray apparatus-to produce accuratealignment of the guide wire W with the axis of the fractured bone. The apparatus may be positioned by means of the wires K on the limb or member and adjusted approximately into alignment as best estimated by the surgeon, as described above. X- ray photographs are then taken through the limb with the apparatus in position, the photographs being taken in perpendicular planes. The X-ray photographs show the departure of the device from precise alignment with the axis of the bone and through the use of the photographs it is possible to adjust the frame 21, the carriage 36, the ring 46 and the guide 44, so that the latter is in axial alignment with the fractured bone.

To facilitate adjustment, and ascertain the positions of the various elements, the supporting frame 10 may be provided with a scale consisting of a series of notches 72 in its lower surface which show up in the X-ray photograph and permit the proper adjustment of the frame 21. Also the protractors may be provided with a scale consisting of the openings 73 in predetermined angular spacing to enable angular adjustment of the guide tube 44.

The device described above is compact so that it can be easily seen in the X-ray photographs and light in weight so that it may be readily applied to the fractured member. It is easily disassembled for sterilization and may be formed of any of a number of different types of metals such as stainless steel, aluminum or the like. depending upon requirements.

The device is of course, susceptible to considerable modification, especially in the design and arrangement of the protractor elements, and in their type of support for the guide tube. For example, as shown in Figure 7, the arcuate bars of the protractors 75 and 76 may be provided with arcuate slots 77 and 78 to receive the ends of the clamping screws 79 and 80 which are threaded into an enlargement 81 on the upper end of the guide tube 82 and bear against the protractors when tightened. The use of such individual clamping screws permits independent adjustment and locking of the guide tube relative to each of the protractors, i.-e., the guide tube may be locked to one protractor element but left movable with respect to the other for further adjustment before locking.

The retaining means for the ball can also be modified as illustrated in Fi ure 8. In this form of the device, the transversely adiustable carriage 85 is arranged to receive the ring 86 in which the ball 78 and uide tube 88 are mounted. The ring 86 is rotatable in the carriage 85 and can be locked in position by means of the thumb screw 89 threaded through a side of the carriage. The ball 87 is received between the converging arms 90 and 91 which support a protractor are at their outer ends. The lower ends of the arms 90 and 91 are provided with concave edges 92 and 93 conforming to the surface of theball 87. The ball may be slipped sideways between the arms and the arms then positioned in the circular opening of the ring 86. The arms are secured in the.

ring, with capacity for pivotal movement, by means of the pivot pins 94 and 95 on the inner ends of the screws 96 and 97 which are threaded into radial openings 98 and 99 in the ring 86. The pivot pins 94 and 95 thus serve to retain the arms 90 and 91 in the ring 86 and the concave edges 92 and 93 retain the ball 87 also in the ring 86. The ring 86 may be retained in position in the carriage 85 by means of the removable retaining ring 100 in the upper surface of the carriage 85.

The overall size of the protractor elements may be varied as required but preferably are relatively small, i. e., on the order of 2" to 3 /2" in overall height, to make possible their registration on the X-ray plates or films. I

The new device makes possible the accurate positioning of the guide tube with respect to the axis of the bone and particularly facilitates the positioning of the guide pin by means of X-rayphotographye- It will be understood that when the guide pin has been'driven into the bone along its axis, the protractor device will be removed by .loosening the thumb screws which secure it .to, the positioningwiresK and the bone nail canthen be driven. alongtheguide wire. W to fix the fracture, in the usual way. The positioning of the nail is dependent upon the accuracy with which the guide wire is driven into the bone so that the positioning of the guide wire is of yital importance-in operations of this type. The present apparatus fulfills all the requirements for accuracy and ease of operation while assuring a stable base for the insertion of the guide wire.

It will be understood that the device is susceptible to considerable modifications in details of construction, in its size and in the materials from which it is made. Therefore the forms of the invention described herein should be considered as illustrative and not limiting the scope of the following claims.

I claim:

1. A device for aligning and inserting nail guides comprising a first rectangular, open frame member having elongated opposite sides and shorter opposite ends, means on said member to receive pins to secure the frame to a fractured bone, a second open frame member mounted between the elongated sides of the first frame member and slidable lengthwise thereof, means on said device for fixing said second member with respect to said first member, a carriage mounted slidably in said second frame member for movement at substantially a right angle to the direction of movement of said second frame member, means on said device for fixing said carriage relative to said second member, a guide tube for a nail guide pin mounted in said carriage for substantially universal movement relative thereto and projecting outwardly from said carriage, and a pair of right angularly related protractors pivotally connected to said carriage for movement about right angularly related axes substantially in the plane of said carriage, said guide tube being adjacent to and guided by said protractor members, and means on said device for fixing said guide tube relative to each of said protractor members.

2. The. device set forth in claim 1 comprising means detachably connecting said means on said member to receive pins to said ends of said first frame member in different positions along the lengths thereof.

3. The device set forth in claim 1 comprising a ring member mounted for rotation in said carriage, a ball and socket connection between one end of said guide tube and said ring member connecting them for relative substantially universal movement and means on said de vice-for retaining said ring member against rotation relative to said third member.

4. The device set forth in claim 1 in which said guide tube has a ball member on its inner end and each protractor comprises a pair of spaced apart substantially parallel arcuate bars disposed on opposite sides of said guide tube, and radius rods connected at their outer ends to opposite ends of said bars and having their inner ends pivotally supported by said carriage, said inner ends being concavely curved to fit and support said ball member in said carriage, the radius rods connected to bars of one protractor being shorter than the radius rods connected to the bars of the other protractor to permit the protractor members to move about said right angularly related axes without interference.

5. The device set forth inf claim (11 in which beach prfir References Cited in the file of this patent tractor comprises a pair 0 space apart su stantia y parallel arcuate bars disposed on opposite sides of said UNITED STATES PATENTS guide tube, radius rods connected at their outer ends to Number Name Date opposiltle ends of galgd bill: and havinhg theiir innedr ends 5 2,200,120 Nauth May 7, 1940 pivota y supporte y sai carriage, t e ra ius ro s connected to bars of one protractor being shorter than the FOREIGN PATENTS radius rods connected to the bars of the other protractor Number Country Date to 1pelrmit thedprotractolrls to movef about saig right an; 10 910,763 France Feb. 11, 1946 gu ar y relate axes wit out intere erence, an a pair 0 thumb screws carried by said guide tube, each screw OTHER REFERENCES being engageable with a corresponding protractor to lock The Lancet for July 20, 1935, pp. 129-131. the guide tube to the protractors. The Journal of Bone and Joint Surgery for Nov. 1948,

advertising page 25. (Copies of these publications in 16 Scientific Library.) 

